Dust collector



Wm BT NM 0 FT n: Am 7 2 9 l 8 2 e n u J Filed Dec. 2. 1925 2 Sheets-Shea! l FIE-LI.

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2 sheets-snout Filed Dec. 2. 1925 INVENTOR- m a. fzur 6 m 6 m w Patented June 28, 1927.

ARTHUR r. NESBIT, or WILKiNSBUBG, PENNSYLVANIA.

' DUST COLLECTOR.

Application filed December 2, 1925. Serial No. 12,700.

My invention relates "to the centrifugal separation of the components of a fluid stream, and finds practical application in dust collectors for coal houses, blast ,furnaces, and other such particular uses. The objects in view are simplicity of structure and efficiency, to achieve in large measure the end in view.

In theaccompanying drawings Fig. I is a. View in vertical section of a dust collector of my invention, designed for service in a coal house, and this embodiment will serve in an exemplary way to illustrate my invention. Fig. II is asectional View on the same plane of the lower continuation of a chamber whose upper part appears .in Fig. I. Fig. III is a view in vertical section, on a plane at right angles to thatof Figs. .1 and 11, showing a certain connectionv of suctiontransmitting means. j 1

A stream of air, initially laden with coal dust but-ultimately relieved of its load, or

substantially so, is caused to advance from inlet. 1 to outlet 2.. These inlet and outlet passageways areconduits square in. cross section, to whichand from whichroundconduits merge. H From inlet passageway 1 the conduit fans out, that is to say, it narrows in one dimension and widens in the other, so that the stream advancesin a broadband, whose greater transverse dimension is (Fig. I) in the line. of sight. This broad band narrows again and deepens, as it approaches the outlet passageway 2.

flow, of the stream through the conduit; preferably the means employed include a suction fan, beyond the outlet 2, and indicated, diagrammatically at 9.

The conduit which carries the broad, band-like stream is curved on a horizontal axis, parallel to the greater transverse dimension of the conduit;.and in this particular instance the conduit is loop-shaped in the longitudinal plane which is the plane of sec-.

tion of Fig. I. The incoming and outgoing branches, 3 and 4, of the loop are vertically disposed and lie in parallelism and closely adjacent, while the bend 5 of the loop 18 in cross-section substantially semiannular, arching over the horizontal'aXis of curvature. r

- The conduit is of undiminished size, from the intake end of the lOOp to thedelivery end, but, intermediate the ends of the loop, andpreferably toward the down-stream end Any suitable means may be employed for effecting the material under treatment.

of the semi-annular bend, thereis a break;

the outer wall 51 on. the up-stream side ofthe break recedes on a widening spiral, and

overlaps theedge 52 of thewall on the 'downstream side of the break.

remote from the opposite inner wall 53v of the loop at a distance not less than, and preferably equal to, the normalw-id'th of the loop, before the recession of the outer wall began. Thus the conduit continues intwo branches;

the inner branch is, from itsspring, of

cross-sectional area'not less than the normal cross-sectional area of the trunk conduit:

' chamber 6. This chamber 6 is of relatively greater capacity and of greater cross-sectional area than the main conduit." It is air tight, and, as presentlyfwill be more fully explained, a condition of reduced pressure is maintained'within it. J

' The shell of sheet metal which forms the dividing 'wall between the branching passageways, and'whose tip forms the edge 52, may beadjustable in a plane paralleltothe axis of curvature of the loop and substantially tangent to the normal outer wall of the loop at the down-stream end-of its semi-' annular bend. The adjustability maybe accomplished by mounting the shell of metal This edge 52 is alluded-to, on slides. 7. These slides may carry racks 71, and suitable rotatable gear wheels 7 2 may be provided which, enga'ging the racks, afiord means for adjusting the particular position of the edge 52. This minute adjustability. gives adaptability of theapparatus to varying conditions in the And it will be perceived that, in consequence of the particular arrangement and the fact that the shifting is in a substantially tangential plane, the adjustment of the position of edge 52 within limits adequate for the ends indicated. effects no appreciable variation in the distance at which the edge 52 lies remote from the inner wall 53 of the loop. V

. Similarly asone branch is formed, a 13111. rality of branches may be formed, leading from the bend of the loop. Fig. 'Ishowstwo branches. The second sheet metal shell, which terminates ina second edge 54, has ,all the characteristics of the first, and .issimilarly mounted for adjustment. In this case there are two outer, dust-carrying passageways, and, While adifferent particular arrangement may if desiredbe adopted, both branches are here'shown to discharge into' a common dust-collecting chamber V Any preferred particular means may be employed, for collecting and'removing the dust which accumulates in chamber 6. Fig. I of the drawings bears indication that the wide chamber 6 narrows downwardly to a delivery leg, and Fig. II shows the delivery leg 61 to be provided with a double delivery, in the form of two bells 62.

The plurality of delivery bells is a matter which, implies a condition of pressure inequality, and directs attention to the means provided for maintaining within chamber6 a condition of reduced pressure, to the end that the flow from loop 5 through the break in the outer wall and through the branch which widens thence and delivers to chamber 6, shall be smooth, and free of re tardations andeddies. Across the depth of chamber 6 extends a nozzle 8. The passageway 81 from this nozzleopens to a box 82. lVithin the box (see Fig. III) partitions 83 subdivide the space.- An eduction pipe 84 leads from the box, and means are provided for creating a condition of suction within the ecluction pipe. The provision. of the partitions 83 aifords better distribution of the suction condition throughout the length of nozzle 8,.that is to say,'throughout the depth of chamber 6. The fact that chamber 6 is of relatively great capacity brings it about that the dust settles to the bottom, while flow through the nozzleS is :an easy flow of relatively clean air.- 2

Operation isas follows: A stream flowing from 1 to 2 is spread to flow in a wide shallow band, and the band is curved on an axis parallel with its width. he curved stream takes the form of a barrel vault, arched above a horizontally extending axis. As the stream advances through loop5 its burden of coal dust (or burden of other separable and relatively heavy material) will by centrifugal action tend to, segregate, and advance in a layer against the ou-ter'wall of the curve. When the-break in the continuity of the conduit walls is reached, this outer heavier layer flows easily along the widening spiral 51 to whichit clings, while the edge 52 shears it from the main bodyof the stream. The main body of the stream, s0 unburdened, flows on to the'outletQ. The

' segregated stream of coal dust (air-born, of

course) discharges into chamber 6.; The condition of reduced p'ressurewithin chamber 6 has ensured free and easy down-draft discharge. The chamber '6 is large; within it the stream is arrested; the coal dust gravitates to discharge leg 61; while-the unburdened air is sucked out through nozzle 8.

This eduction conduit 84 may be led to passageway 1, and in that case the single fan 9 situated beyond 2 will maintain the conditions described. This particular arrangement is indicated in Fig. I. A separate fan or equivalent means might manifestly be employed for creating suction withinconduit 84.1

Adjustment of edge 52 effects the cutting away of a deeper or shallower layer; of coal dust.

I claim as my mventionz 1. Means for efi'ecting centrifugal segregation and separation of the components of a flowing stream which include a main conduit of undiminished cross-sectional area from its inlet to its outlet end, included between opposite parallel walls and curvedon an axis to which such opposite walls are parallel, the walls of the conduit through-L out the extent of thecurve being '(but for the opening to the branch conduit) eontinn. ous, a branch conduit openlng'through the wall of the main conduit on the outer side of the curve, such branch conduit being, of

increasing cross-sectional area" and being curved ma widening spiral about the same.

axis, and means for causing fluid to stream through the conduit and the branchcondult.

2.lv1eans for effecting centrifugal segregation and separation of the components ofa flowing stream which include a main conduitof undiminlshed ,cross-sect1on'al area from its inlet to its outlet end, included between opposite parallel walls andcurved' on an axis to which such opposite walls are parallel, the wallsof the conduit throughout the extent of the curve being (but for the opening to the branch conduits) continuous, a plurality of branch conduits opening through the wall of the main conduit on the outer side of the curve,

such branch conduits branching in immediate success on from the main conduit, the said branch conduits being of increasing ion cross-sectional area and being curved in' wideningspirals'about the same axis, and means .formaintaining at the delivery ends ofthe main and branch conduits conditions of reduced pressure relatively to thatat theintake end of the main conduit.

8. Means for effecting centrifugal segregation and separation of the components'of V a flowing stream which consist in a curved conduit, in the outer wall of which'a break adjustable in a direction tangentialto wall curvature, and means for effecting stream flow.

Y 4. Means for eifecting centrifugal Segre-- gation and separation of the components of a flowing stream which include a main. conduit of undirninished cross-sectional area from its inlet to its outlet end, included between opposite parallel walls and curved on an axis to which such opposite walls are parallel, the walls of the conduit throughout the extent of the curve being (but for the opening to the branch conduit) continuous, a branch conduit opening through the wall of the main conduit on the outer side of the curve such branch conduit increasing in width betweenwalls parallel with the said opposite walls of the main conduit, a dustcollecting chamber of greater cross-sectional area than the main conduit, to which said branch conduit opens, means for maintaining at the delievery end'of the main conduit and within said dust-collecting chamber conditions of reduced pressure relatively :10 that at the intake end of the main conuit, Y

In testimony whereof I have hereunto set my hand.

ARTHUR F. NESBIT." 

